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为了解决装饰砂浆普遍存在的泛碱难题,以可再分散乳胶粉(SWF-08)、羟丙基甲基纤维素醚(HPMC)、阻碱剂和憎水剂(SWR-100)为影响因素,以14 d拉伸强度和泛碱性为考核指标,采用单因素分析法优选出制备装饰砂浆的最佳配方.结果表明:各种物料对装饰砂浆抑制泛碱作用的大小依次为阻碱剂>HPMC>胶粉>憎水剂;当w(... 相似文献
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聚合物改性砂浆应用范围日趋广泛.通过对可再分散乳胶粉5044N、水泥、石英砂等配制不同砂浆进行研究,分析得出各种材料的作用,提出了灰砂比、乳胶粉掺量对砂浆影响至关重要. 相似文献
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可再分散乳胶粉具有极突出的粘结强度,可提高砂浆的柔韧性,赋予砂浆优良的耐碱性、防水性、可塑性、耐磨性和施工性。本文研究了可再分散乳胶粉对水泥砂浆拉拔强度、热循环后拉拔强度、冻融循环后拉拔强度、浸水后拉拔强度以及破坏方式的影响。结果表明:可再分散乳胶粉对水泥砂浆在不同处理条件下的拉伸强度和粘附强度有明显的改善效果。 相似文献
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制备可再分散苯-丙乳胶粉的干燥温度探讨 总被引:1,自引:0,他引:1
采用喷雾干燥法制备苯-丙可再分散乳胶粉.探讨了干燥室进口温度对制备苯-丙可再分散乳胶粉及其性能的影响.结果表明,进口干燥空气的温度对乳胶粉的外观、粒径、含水率、再分散性、成膜性能、吸水率有较大影响.干燥温度升高,可再分散乳胶粉含水率降低,再分散液粒径减小,再分散性、成膜性都变好,吸水率提高.但温度过高(160 ℃)和过低(100 ℃)会使乳胶粒子在干燥过程中形成粒径较大的聚合物颗粒,导致粉体滤渣含量增加,对于苯-丙乳液来说,适当的喷雾干燥温度是120~140 ℃.红外光谱图表明:在100~160 ℃下的干燥没有明显改变乳胶粒子的分子结构.SEM图分析表明:干燥温度越高,再生膜越致密. 相似文献
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将可再分散沥青粉末(EAP)、醋酸乙烯酯-乙烯共聚物(VAE)乳胶粉、苯乙烯-丙烯酸丁酯共聚物(SBA)乳液作为外加剂分别掺入水泥砂浆,通过热处理前后的吸水率测试、胶砂强度测试和微观形貌分析,研究了不同聚合物对水泥砂浆在70℃的耐热老化性能的影响。结果表明:试验采用的聚合物均可降低砂浆吸水率,且吸水率随聚合物掺量的增加而降低。SBA乳液的成膜性能优于粉体聚合物,因此SBA改性砂浆的表面防水效果最佳;两种可再分散聚合物粉末对比,同期热老化后EAP对砂浆防水改性效果优于VAE。经热老化后,沥青组分高温下具有一定的黏流性,EAP改性砂浆热老化后抗压强度降低,随EAP掺量增加,抗折强度先升高后降低,其强度变化主要体现为沥青组分在高温下的作用特点,VAE改性砂浆及SBA改性砂浆热老化初期聚合物膜结构阻碍水分迁移,热老化后期柔性的聚合物膜结构破坏造成强度高于热老化前的强度,其强度变化主要体现为传统聚合物改性砂浆的特点。 相似文献
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水泥基腻子面漆二合一内墙涂料的制备 总被引:1,自引:1,他引:0
以自制的可再分散乳胶为主要成膜物质,结合水泥水硬性无机粘结剂制备了腻子面漆二合一内墙涂料,重点讨论了可再分散乳胶粉、纤维素醚、粉状憎水剂对涂膜性能的影响.实验结果表明,可再分散乳胶粉及其用量对腻子面漆二合一涂料性能具有重要影响,当其用量为4%~6%时,涂膜具有良好的综合性能;纤维素醚能明显改善涂料的施工性能和保水性能,其最佳用量为0.3%;粉状憎水剂显著提高涂膜的耐水性和耐洗擦性能,其用量为0.3%时可达到很好的效果.产品综合性能达到或超过国标JG/3049-1998N型和GB/T 9756-2001优等品指标值. 相似文献
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以陶瓷抛光砖粉为辅助胶凝材料,通过单掺及复掺陶瓷抛光砖粉和聚丙烯纤维,研究了不同掺量的聚丙烯纤维及陶瓷抛光砖粉对砂浆稠度、抗压强度、抗折强度、干缩率和抗冻性的影响.研究结果表明:在单掺条件下,随陶瓷抛光砖粉掺量的增加,砂浆稠度变大;随聚丙烯纤维掺量的增加,砂浆稠度变小.在复掺条件下,当聚丙烯纤维掺量达到1.5 kg/m3时,纤维掺入所导致的粘聚性增大成为主导因素.陶瓷抛光砖粉的掺入能够提高砂浆力学性能,且随其掺量增加,砂浆抗压强度与抗折强度增大;砂浆抗折强度随聚丙烯纤维掺量的增加而增加呈上升趋势,但砂浆抗压强度随纤维掺量的增加呈先降后增趋势.陶瓷抛光砖粉和聚丙烯纤维均能有效抑制砂浆的干缩,降低砂浆经冻融循环后的抗压强度损失率,提高砂浆的抗冻性能. 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献